Summary This application, aims to provide educational activities that encourage individuals from diverse backgrounds, including those from groups underrepresented in the biomedical and environmental sciences, to pursue further studies or careers in environmental health research. After securing funding from the NIH through this program in 2015, we successfully launched the Program to Inspire Minority Undergraduates in Environmental Health Science Research (PrIMER). With this competitive renewal we aim to continue the program's goal to increase the diversity of the environmental and health research workforce in the environmental health sciences (EHS) and ensure that future generations of environmental health researchers and public health practitioners come from the entire pool of talented individuals, including underrepresented minorities, persons with disabilities, and the socioeconomically challenged. Environmental health problems are increasingly complex and require the successful integration of environmental and health sciences, among other disciplines. Research has demonstrated that diverse research teams with respect to race, ethnicity, gender, sexual orientation, other are better at solving complex problems. To make headway against our toughest environmental health challenges, it is thus essential that research teams are diverse in membership, interdisciplinary, and grounded in solid knowledge and state-of-the art methods. For this new cycle, we thus propose to expand our training opportunities. In addition to maintaining our outstanding training and research opportunities in the Department of EHS at the Mailman School Public Health, the students will have new formal training opportunities at the Earth Institute, the Columbia University Irving Medical Center (CUIMC), and other departments at MSPH (Epidemiology and Sociomedical Sciences). This program aims to increase the number of diverse students pursuing EHS related careers; to provide a robust research and education experience for participants in EHS related topics, by having students work closely with faculty mentors and their teams on research projects during the two years in the program; and to provide participants with the skills needed to help create competitive applications for admission into programs for graduate studies, prioritizing fields relevant for EHS, and to provide guidance throughout this process to ensure their success. With the achievements and experience of initiating and running the PrIMER Program for the past 5 years, and with feedback from students, participating faculty and our advisory board we are positioned to move ahead with a better, stronger and more comprehensive program that covers the many aspects that comprise EHS research. Columbia's reputation as a major research hub, its expert faculty, the extensive NIEHS research portfolio, and its location in the ethnically diverse, culturally rich center of New York City, make it an ideal place to carry out this work enabling us to contribute to NIEHS's goal of building a more diverse scientific workforce.